1. Scope of Invention
This invention relates generally to endodontics and more particularly to a bacterialcidal lubricant for use in facilitating the removal of the nerve from the root canal of a tooth during endodontic therapy.
2. Prior Art
Thorough cleaning and enlarging of the root canal in conjunction with endodontic therapy has a major impact on the success of such treatment. However, due to the confined work area and the size of the equipment required for this procedure, success is not always assured.
The difficulty and importance of both removing debris and enlarging the root canal or nerve passageway, while also introducing a bacterialcidal component has been described in an article entitled "EDTA and Urea Peroxide for Root Canal Preparation" by G. Stewart in an JADA, VOL. 78, February, 1969. Summarizing this article briefly, EDTA (Disodium Ethylenediamine Tetra Acetate) was introduced in 1957 for removing calcium from both dentin and the concretions within the pulp. EDTA permits the use of reamers and files to clean and enlarge the root canal more readily and has been shown to have antimicrobial activity.
In 1961, Stewart and others introduced urea peroxide in an anhydrous glycerin base as an aid in treating infected root canals. The urea peroxide solution was stable at room temperature, while the glycerin base acted as a lubricant. Another compound, sodium hypochlorite solution reacts with hydrogen peroxide, breaking it down and liberating great quantities of oxygen. In doing so, this combination is useful in floating debris from a root canal, as well as bleaching and deodorizing the tooth. The Stewart article goes on to describe the combination of EDTA and urea peroxide as being an effective aid in cleaning and enlarging root canals. The combination also exhibited good chelating properties, helped float debris from the root canal and altered the surface of the root canal to exhibit complete penetration of medication into the tooth,
Although this treatment is still now utilized in more current endodontic procedures, nonetheless it exhibits limitations of EDTA softening of tooth structure causing ledges or perforations to occur which my previous patent overcame.
My previous U.S. Pat. No. 5,149,536 provides a more effective lubricant for reducing the friction between the walls of the root canals and the file, while also providing a bacterialcidal effect. However, a problem has developed in marketing and distributing the product embodied in the claims of this '536 patent. This formulation breaks down if frozen during shipment. This original product lost most of its firmness and underwent a change in color as well, changing from a grayish off-white firm emulsion to a thin, milky-colored liquid rendering the product unusable for its intended purpose.
Applicant is also aware of U.S. Pat. No. 4,981,686 to Hardy which teaches a vaginal lubricant having some of the ingredients of the present invention, but otherwise, having nothing to do with the present invention.